Expert Interview — Qualitative Knowledge Elicitation from Domain Specialists

In a standard qualitative or phenomenological interview the respondent's subjective experience is the object of study. In an expert interview the respondent is treated as a proxy for a broader institutional or professional knowledge domain — their personal biography is background, not foreground. The analytic interest lies in what they know about a field or process, not in how they experienced their own life. This shifts the sampling logic (purposive by role rather than by experience), the question design (process- and domain-oriented rather than experience-eliciting), and the analysis (cross-case mapping rather than essence description).

There is no universal threshold, but 10–30 interviews is the range most commonly cited for a study with a well-defined domain. The guiding criterion is thematic saturation — the point at which additional interviews are not introducing new perspectives, positions, or information relevant to the research question. Domains with high internal diversity (e.g., a multi-sector policy arena) require more interviews than tightly bounded specialist communities.

Access and candour are persistent challenges. Strategies include: institutional letters of support, assurances of anonymisation, conducting the interview in a neutral rather than institutional setting, emphasising the academic rather than evaluative purpose of the research, and leveraging gatekeepers or shared professional networks for introductions. Even with assurances, some topics will elicit carefully managed responses; triangulating expert accounts against documents and other informants helps identify what is being left unsaid.

Yes. Video calls (Zoom, Teams) and telephone interviews are well-established alternatives when face-to-face access is impractical due to geography, time constraints, or respondent preference. Research comparing modalities suggests that the depth and candour of expert accounts are not substantially diminished in remote formats, provided the interviewer establishes rapport at the outset and the conversation is not interrupted by technical difficulties. Transcription and analysis procedures are identical regardless of modality.

Contradictions are analytically valuable, not problems to resolve away. They typically reflect genuine differences in institutional position, professional perspective, or strategic interest among experts. The appropriate response is to map the contradiction explicitly — to ask why informants in different roles or organisations hold divergent views — and to treat divergence as evidence of contested knowledge, competing interests, or structural tensions within the field. Forcing a false consensus by averaging accounts misrepresents the actual knowledge landscape.